This paper studies the assignment of decision makers to two committees that make decisions by a simple majority rule. There is an even number of decision makers at each of various skill levels and each committee has an odd number of members. Surprisingly, even with the symmetric assumptions in...

Collective contests are examined permitting heterogeneity of stakes within every competing group. Our first concern is whether unequal distribution of stakes in a group can enhance its win probability. Our second concern is whether a large stake in a group can be individually disadvantageous. We...

We determine the scoring rule that is most likely to select a high-ability candidate. A major result is that neither the widely used plurality rule nor the inverse-plurality rule are ever optimal, and that the Borda rule is hardly ever optimal. Furthermore, we show that only the...

We propose the concept of level r consensus as a useful property of a preference profile which considerably enhances the stability of social choice. This concept involves a weakening of unanimity, the most extreme form of consensus. It is shown that if a preference profile exhibits level r...

Interest groups are introduced in a spatial model of electoral competition between two political parties. We show that, by coordinating voting behavior, these interest groups increase the winning set, which is defined as the set of policy platforms for the challenger that will defeat the...

Interest groups are introduced in a spatial model of electoral competition between two political parties. We show that the presence of these interest groups increases the winning set, which is the set of policy platforms for the challenger that will defeat the incumbent. Therefore, interest...

We consider a framework where the optimal decision rule determining the collective choice depends in a simple way on the decision makers' posterior probabilities of a particular state of nature. Nevertheless, voting is generally an inefficient way to make collective choices and this paper sheds...

We consider a collective choice process where three players make proposals sequentially on how to divide a given quantity of resources. Afterwards, one of the proposals is chosen by majority decision. If no proposal obtains a majority, a proposal is drawn by lot. We establish the existence of...